Miscarriage Pending?

Greetings. I'm 5 weeks 5 days, but had some bleeding so went to ER today, they took blood. My hcg is 2259, and they saw a sac but no baby, and my cervix is closed. I've had no clotting, just blood after intercourse and then last night I gushed out some when I was throwing up from a stomach virus. I'm terrified. As all of you feel about your situation, this baby is so very wanted. I'm suppose to stay calm (not my strong point) and go back in two days to have hcg checked. I guess I'm looking for encouragement. Thanks